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Note

  • This code has been compiled to show the internal calculations of the addresses of array elements like this: 824.
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  Value and type of last evaluated expression: Address of array element: Address of array elementx:  (none)

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Code

 Header...

// Return the scalar (dot) product of two vectors

 float dotprod(float v1[],float v2[],int n){
»  float res=0;

»  for ( int i=0;i<n; ++i) 
    res+=v1i*v2i;

»  return res;
}
 ... 


#define VECLEN 2
#define NVECS 3
 int main(){
»  float dot[NVECS][NVECS], vector[NVECS][VECLEN]=
    {1.5,3.9,4.7,7.2,2.1,5.13,};
»  int j, k;

»  for (j=0; j<NVECS; ++j) {
»    for (k=j; k<NVECS; ++k) 
      dot[j]k=dotprod(vectorj, vectork, VECLEN);
  }

»  return 1;
}
 ...
Memory

dotprod()

128
129
130
131
132
133
134
135
v2 = 224
v1 = 224
136
137
138
139
140
141
142
143
?
?
?
?
res = 0
176
177
178
179
n = 2

dotprod()

128
129
130
131
132
133
134
135
v2 = 224
v1 = 216
136
137
138
139
140
141
142
143
?
?
?
?
res = 0
176
177
178
179
n = 2

dotprod()

128
129
130
131
132
133
134
135
v2 = 232
v1 = 232
136
137
138
139
140
141
142
143
?
?
?
?
res = 0
176
177
178
179
n = 2

dotprod()

128
129
130
131
132
133
134
135
v2 = 216
v1 = 216
136
137
138
139
140
141
142
143
?
?
?
?
res = 0
176
177
178
179
n = 2

dotprod()

128
129
130
131
132
133
134
135
v2 = 232
v1 = 216
136
137
138
139
140
141
142
143
?
?
?
?
res = 0
176
177
178
179
n = 2

dotprod()

128
129
130
131
132
133
134
135
v2 = 232
v1 = 224
136
137
138
139
140
141
142
143
?
?
?
?
res = 0
176
177
178
179
n = 2

dotprod(): for()

144
145
146
147
i = 0

dotprod(): for()

144
145
146
147
i = 0

dotprod(): for()

144
145
146
147
i = 0

dotprod(): for()

144
145
146
147
i = 0

dotprod(): for()

144
145
146
147
i = 0

dotprod(): for()

144
145
146
147
i = 0

main()

208
209
210
211
212
213
214
215
j = -538248967
k = -46473827
216
217
218
219
220
221
222
223
vector[0][0] = 1.5
vector[0][1] = 3.9
224
225
226
227
228
229
230
231
vector[1][0] = 4.7
vector[1][1] = 7.2
232
233
234
235
236
237
238
239
vector[2][0] = 2.1
vector[2][1] = 5.13
240
241
242
243
244
245
246
247
dot[0][0] = 2.5462e-08
dot[0][1] = 3.97963e+33
248
249
250
251
252
253
254
255
dot[0][2] = 1.65772e+27
dot[1][0] = 1.02965e-17
256
257
258
259
260
261
262
263
dot[1][1] = 2.38715e+28
dot[1][2] = -1.58221e+25
264
265
266
267
268
269
270
271
dot[2][0] = 7.18707e-08
dot[2][1] = -1.90287e+17
272
273
274
275
dot[2][2] = -4.49525e+33

NB: the actual memory address of each variable is the
address shown plus 4293556696 (0xFFEA79D8).

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